From what I remember
Firstly start teaching your child to "push" their pants down by themselves (children don't click with "pull" them down, as that's not action we really use)
Clear your diary - completely.
The child stays naked at home
You do absolutely nothing but watch them, every child has a cue before they wee/poo, your job is to watch for it.
Once you have it, every time they display it put them on potty, lots of praise if anything comes out.
Then you start to simply encourage them to use the potty, not constant reminders or putting them on jt, that's not teaching them to recognise the feeling of needing a wee and associating it with going the potty. When you see the cue, "do you need the potty/wee" if they go massive praise, once a few are in the potty, stop the reminders.
Once they are 80% getting in the potty, then you take them out. They must try for a wee before you leave and they wear no underwear. The first outing is literally a few minutes around the block, when you get back in, you say for them to try for a wee. Don't leave until they have tried for a wee, it get them in the habit. Then your next outing is maybe the supermarket with a toilet in it, so you try for a wee before you leave then when you get to the supermarket - gets them in the habit and used to going to the toilet on different environments. Tell them to tell you if they feel they need a wee. Lots of praise and encouragement each time they try, and each journey that is accident free.
Once they are happily taking themselves and happy with pushing down their pants and can do it with loads of time left to still get their pants down and wee in the toilet, not in their pants while trying to get them down as they've left it too late, then they have underwear and trousers/shorts
This is a very brief, of what I can remember, sorry it's not more concise, but that was the jist.
I think i lined my car seat with a dogs puppy pad, luckily it wasn't necessary but just in case.